Step-by-step explanation:
-3(-x -3y) = 3( x +3y) = 3x+9y
97 rounds up to 100
78 rounds up to 80
100x80= 8,000
estimate=8,000
97x78=7,566
product=7,566
Answer: 56
Step-by-step explanation:
Given : Number of red marbles = 5
Number of green marbles = 3
Number of yellow marbles = 3
Number of orange marbles = 3
Number of red and green marbles = 5+3=8
Now the possible number of sets (combinations) of five marbles are there in which all of them red or green will be :-

Hence, the number of sets of five marbles in which all of them red or green=56